Projectile.



J. B. SEMPLE.

PROJECTILE.

APPLICATION FILED JAN.29, 1915.

mmsae I 1 Patented-Feb. 22,1916.

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5i L6 4 r 6 II- *l3 5 I n :1 E3 F WITNESSES INVENTOR JOHN B. SEMPLE,SEWICKLEY, PENNSYLVANIA.

rnoJno'rILE;

Specification of Letters Patent.

Patented Feb. 22, 1916.

Application filed January 29, 1915. Serial No. 5,022.

To (1.6L w/wmz't may concern:

Be it known that I, JOHN B. SEMPLE, re-

siding at Sewickley, in the county of Allegheny and State ofPennsylvania, a citizen .of the United States, have inventedordiscovered certain new and useful Improvements in Projectiles, ofwhich-improvements the following is a specification.

My invention relates to improvements in projectiles. It is illustratedin the accompanying drawings, in which Figure 1 is a view inlongitudinal central section of the posterior end of a projectile inwhich my present invention is embodied; Fig. 2 is a view incross-section of the fusestock of the projectile of Fig. 1,the plane of.

section being indicated in Fig. 1 by the line IIII; and Fig. 3 is a viewin section of a locking block in detail in one specific permissibleform.

In a co-pending application, Serial No. 835,131, filed April 29, 1914:,and allowed August 5, 1914, I have described and claimed a projectileincluding in its structure a movable meinber controlling detonation inthis respect: When this movable member is in one position and thedetonator explodes, detonation will not be imparted to the burstercharge; but when'the movable member is in its alternate position,explosion of the detonator will result in communication of detonation tothe burster charge. One specific alternativemeans of accomplishing thisend is illustrated" and described in the application referred to andspecifically claimed in the more limited claims of that application.That specific means includes in the structure a burster charge and adetonator charge movable the one with respectto the other from remote toadjacent position'-the objectbeing that, in case of premature explors'ion of the detonator (which in the present state of the art consistsof unstable and dangerc-us material), the burster charge will be safefrom explosion; but, when once the projectile is fired from a gun, theconditions incidnt to firing and flight will bring det onator andburster charge into relative pos'itions for service; so that, when uponimpact the detonator is exploded in proper and intended manner,"explosionof t e .burster charge will follow in regular course.

My present invention is another specific means of accomplishing the sameends. Or, in other Words, it is another specific invention under thesame generic invention noted above. My present invention, like myearlier invention referred to, employs a movable member, and thismovablemember is controlled "in the'same manner as in the earlier case; but'inthis case the detonator is stationary, and the movable member (insteadof carrying the detonator from remote ,position to a position ofoperative proximity to the burster charge)- serves to control the'continuity of a path of detonation transmission, from detonator toburster charge, and in its movement to; carry a section in a train ofdetonation. Normally, and until theprojectile has been fired, this trainis ins terrupted; as the projectile is fired froma gun and flies throughthe air this train is made continuous; so that, whereas before firingexplosion of the detonator will be without efi'ect upon the burstercharge, after the projectile'has been fired from a rifled gun theensuing explosion of the detonator will be imparted in intended mannerto the burster charge. Among the advantages of this arrangement over thespecific arrangement described in detail in my earlier application,referred to, are-these: The problem how best to arrange the detonatorwith its adjacent safety chamber is simplified by the elimination of onefactor. Again, the detonator being stationary, Whatever liability tomiss fire may be inherent in the traveling detonator is avoided;premature detonation of the burster-charge is more certainly guardedagainst. Finally, as compared with a runway for a movable 'detonator(which must' be straight and relatively large) the detonation pathwayfrom a stationary detonator to the burster charge may be small and (iffor other reasons desirable) may be tortuous. i

Detonation is a phenomenon which certain substances exhibit, ofexploding, under proper conditions, with extraordinary intensity. A massof black powder explodes progressively. The chemical changes advancefromthe point at which the impulse is applied to the remote portions ofthe mass; and, thoughthis progression is'a very rapid one, it is still aclearly discernible progression. When a mass of picric acid,

by way of comparison, is detonated, the

chemical breaking down and rearrangement of elements (which presumably-must be progessive also) advanceswith Such swift:

ness throughout the mass that the whole body seemsto have beenresolv'ed'instanta'neously; the progressionis .so rapid that it cannotbe detected. Furthermore, detonation of such 'a substance as picric acidis a phenomenon of enormously greater power and'intensity than the;explosion of a like quantity of black powder. Substances socharacterized are in common speech classed as high explosives; their.distinguishing characteristic is their ability to detonate.

some substances capable of detonation are, under all ordinaryconditions, quite'inert and harmless; so true is this that certain ofthem were long'known-to the useful arts because of other properties andcharacteristics, while their explosive nature remained quiteundiscovered. The substances of which I am speaking may be handled withsafety; no ordinary shock explodes them; they are combustible; some ofthem may on ignition be exploded in alowpower 'explosionan explosion ofsecond magnitude-but none of them can be exploded in an explosion offirst magnitude- 2'. e. detonated-on ignition. The flash of a percussioncap, such as is ordinarily used to fire the burster charge of anexplosive projectile, has no power upon them to effect. detonation. Theycan be detonated only by certain other high explosivesand the num- -beravailable is smallwhich possess this peculiarity: they detonate onignition. Fulminate of mercury is such a substance; lead nitrid isanother. These substances are not practicable as material for theburster.

charges of projectiles; they are too sensitive; the danger incident tohandling them in large quantities forbids. But though not.

available as burster-charge material, these substances becomeserviceable 1n the manufacture of explosive projectiles, because oftheir peculiar property mentioned; their use is indeed indispensable inproducing practically operative explosive projectiles charged with sucha material as tetra-nitro-analin, for example. That material 'is notresponsive to the*fiash of .a percussion cap; or, at least, it cannot bedetonated,.asa charge of black powder is expl'oded, by the flash-of apercussion cap. By introducing into the make-upof'a projectilea body ofsuch material as fulminate of mercury and by placing it inintermediate'position,where it will he subjected to the flash of apercussion cap In this tinuous.

properly fired and where it is in detonationiiimpar'ti'ng relation tothe burster charge proper; a high-explosive shell may be produced. Theintermediate charge of fuhninate need not be, and for obvious reasonswill not be, large. hen then means are provided which normally preventthe transmission of the impulse of detonation from the charge offulminate to "the burster charge (so that in case of premature andaccidental detonation of the sensitive fulminate the burster charge willnot be detonated) but .means which allow such transmission whentheproper time has come, it is manifest that a practical high-explosiveshell has been produced.

Various expedients have been adopted to keep the fulminate charge(commonly called the detonator charge or detonator) and the burstercharge normally separate and to bring them into detonation-impartingrelation at the proper time. These prior expedients, so far as I amaware, have involved the provision of a movable detonatoi which mayadvance in'a runway from a remote and relatively harmless position to aposition where, on firing, it will impart detonation to the burstercharge. And of course, in such an arrangement, provision is made for theproper control of the detonator in its movement.

' Now my present invention, while in one aspect it stands related as Ihave said as speciesto genus to an earlier invention involving a movabledetonator. in another aspect is characterized by this: It does notrequire that (letonator and burster charge be relatively movable. Itconsists, essen' tially. in arranging detonatorand burster charge at asuitable interval, in providing a pathway for detonation transmissionfrom.

one to the other, and in supplying means for alternately and at propertnnes mterruptlng that pathway and making it con- 'Detonation is a verydifferent thing from the flash of a percussion cap. A flash is,essentially, a flame a body of incandescent gaswhich, proceeding fromits source, may travel across Wide air spaces and through long emptyducts; detonation is a force, an impulse, a'vibration, like electricity,and is communicated through suitable bodies which are, indeed,conductors of detonation. A flash will leap through a passagev onationmay be freely carried for indefinite distance, if only the materialthrough which it is carried be proper and be substantially. continuousin extent; and ordinarily it will be true, and as I now practioe myinvention it is true, that the pathway which in my projectile I providefor detonation transmission would not afford passage of the fiash of aprimer cap nor transmit its effect, v

In the accompanying drawings 1 indicates a burster-charge chamber withinthe projectile, and 2a fuse stock for the fuse which is tov detonate theburster chargev within chamber 1. B is a booster charge, that is, areinforcing charge, intended to receive detonation from the detonatorand to impart detonation to the charge within chamber 1. This, undervexisting practice,

will ordinarily consist of tri-nitro-toluene premature firing .of thedetonator the gases of. explosion will fill chamber 14 but (the partsabout to be described being in safety position) the explosion will haveno effect upon the burster charge. It is further to beobserved thatthe-safety chamber 14 is a closed chamber within the fuse stock andwhen. the parts are assembled within the body of'the projectile. Sinceit is a closed chamber there can be no danger, in case of the prematurefiring of the detonator, of the spit-ting'out of flame and gas and ofthe attendant danger to life and limb of those who have to do with thehandling of these articles.

'A pathway 13 for detonation transmis- SlOIl leads from the cylindricalchamber in which detonator D snugly fits to the cham-.-

ber containing the burster charge B. This pathway may be direct,ortortuous, as size and relative dimensions may require. I

Acrosspathway 13, and in'a'more or less 1 exactly radial direction(preferably exactly radial) with respect to the axis 'of rotation of thestructure, extends a runway 3. In this runway is arranged a movablemember 6, which under centrifugal force of the .projectile in flighttends to move to the outer end of the runway, but which is normally heldat the inner end by a pair of springback centrifugally releasing bolts1, precisely such as are described in my copending application namedabove. The movable member 6 ispreferably recessed to receive tionreferred to.

the bolts, in the manner illustrated in the drawings, and as describedin the applica- When the movable member 6. is retracted and stands inthe locl rd position shown in Fig. 1, the pathway for '1 detonationtransmission is interrupted, so that the explosion of detonator D(should it prematurely occur) cannot be imparted to fire the charge B;but when bolts 4- reoede,

unlocking member 6, and when member 6 slides outward finder centrifugalforoe,. a detonation pathway in its body is brought into register withthe previously interrupted pathway 13, and then the continuity of thepathway is established from detonator D to buster, charge B. The portionof the path-j way which is formed 1n the body of member 6 mayconveniently encircle the member 6 being in this case a filling ofdetonation transmitting material packed or molded into the encirclinggroove 12, which has this advantage: However the member 6 may turn onits own axis, registry of the portion of the pathway formed in member 6with the portion of the pathway formed in the partition wall andindicated 13will be certain when the movable member is shifted in themanner and to the ends described.

A locking member 7 may lie within the 1n- .ner end of member 6; and, byextending the runway 3 across the center of rotation, this lockingmember 7 will under centrifugal force crowd against the inner end of therunway and be retracted from member 6 as that member moves outward, andthen having escaped from the recess which held it, it

may so move (by special shaping, if found necessary) that it will nolonger stand 'alined with the recess, but. will thereafter serve as alocking block, to prevent returnof the member 6, now moved to armedposition. The locking member specifically illustrated in Fig. 3 ismerely exemplary. It is so shaped (having an oblique rear surface) thatwhen fully withdrawmfrom the member 6 it will tip and will not again bein a position to reenter the recess which formerly contained it.

The pathway for the transmission of detonation from detonator to.,burster charge may be such as the intelligent designer may select; itmust be of material suitable for detonation transmission as shown (andthis is my preference) it is a narrow duct filled with high explosive(preferably tri-nitrotoluene); and, furthermore, the groove in themovable member 6 is in like mani1er filled with high explosive. 'Whenthe duct and groove are brought to register one with the other, there isformed a continuous line for detonation transmission; The pathway fordetonation transmission from detonator to burster charge consisting ofa. column of such material as tri-nitrotoluene cannot be penetrated by aflash; ig-

nition started at one end cannot burn through. Furthermore, thin septaof metal, if interposed and dividing the column at intervals-thoughmanifestly they would cut off any bodily advance of -fiamewould notprevent transmission of detonation.

I claim as my invention:

, 1. In an explosive projectile the combination of a burster charge ofhigh explosive, a detonator, a path of detonation transmission extendingfrom said detonator to said burster charge, and means for alternatelyinterrupting and making continuous said path.

2. In an'explosive projectile the combination of a burster charge ofhigh explosive, a detonator, a train of detonation transmissionextending from said detonator to said burster charge'a section of saidtrain being movable from a position of interruption to a position ofcontinuity.

3. In an explosive projectile the combination of a burster charge ofhigh explosive, a detonator, a path of detonation transmission extendingfrom said detonator to said burster charge and normally discontinuous, amember movable in sequence on the firing of the projectile from a gunfor establishing the continuity of said path, and means for preventingretrogression of saidmovable member. i w

et. In an explosive projectile the combination of a burster charge, adetonator, a path of detonation transmission leadingfrom said detonatorto said burster charge, a break in said path, a. member movable in suchbreak and responsive within the range of such movement to centrifugalforce exerted upon it on the flight of the projectile from a rifled gun.a centrifugally opening, lock normally holding said movabl member at oneend of the range of its movement, and a centrifugally closing lock forsaid movable member at the opposite end of its range.

In an explosive projectile the combination of a burster charge, asafetychamber, a detonator stationary with relation to and adjacent saidsafety chamber and removed at an interval from said burster charge, apath of detonation transmission leading from said detonator to saidburster charge,

.said path being normally interrupted, and means for establishing thecontinuity of said path.

6. In an explosive pro ectile the combination of a burster charge, aclosed safety.

chamber, a detonator adjacent said safety chamber-,2. path of detonationtransmission normally interrupted extending from said Copies of thispatent may be obtainedfor detonator to said burster charge, and meansfor establishing the continuity of said path.

7. In an explosive projectile the combination of a burster charge, adetonator, an ignition cap, an ignition path from said cap to saiddetonator, a normally interrupted path of detonation transmission fromsaid detonator to said burster charge, and means for establishing thecontinuity of said path of detonation transmission.

8. A fuse stock for an explosive projectile including a substantiallycylindrical body dividedaby a transverse partition wall, a detonatorwithin a safety chamber arranged together with its ignition cap on oneside of said wall, a reinforcing chargearrang ed on the opposite side ofsaid wall, a centrifugal bolt movable in a transverse runway. in saidwall, and a column of detonation-transmitting material contained in partin said Wall and in part in said bolt.

9. In a p-ro ectile'the combination with a .burster charge, a source ofdetonation, and a path of detonation transmission from said source tosaid burster charge, of a cylindrical bolt movable in a runway acrosssaid detonation transmission path said bolt being provided with anencircling path of detonation transmission.

10. In a projectile the combination with a Yburster charge, a source ofdetonation, and a path o-fdetonation transmission from said source tosaid burster charge, of a runway intersecting said detonationtransmission .a larger main body and an attenuated extension, and, incombination with the burster charge so shaped, a detonator arranged atthe remote end of said extension, and a make-and-break device, arrangedin said ex tension of the burster charge.

In testimony whereof I have hereunto set my hand.

7 JOHN B. SEMPLE.

\Vitnesses:

BAYARD HI CHRISTY, FRANCIS J. TOMASSON.

five cents each, by addressing the Commissioner of Patents. Washington,D. 0.

